HIV-1 subtypes among intravenous drug users from two neighboring cities in São Paulo State, Brazil

Abstract

In order to assess the molecular epidemiology of HIV-1 in two neighboring cities located near the epicenter of the HIV-1 epidemics in Brazil (Santos and São Paulo), we investigated 83 HIV-1 strains obtained from samples collected in 1995 from intravenous drug users. The V3 through V5 region of the envelope of gp 120 was analyzed by heteroduplex mobility analysis. Of the 95 samples, 12 (12.6%) were PCR negative (6 samples from each group); low DNA concentration was the reason for non-amplification in half of these cases. Of the 42 typed cases from São Paulo, 34 (81%, 95% confidence limits 74.9 to 87.0%) were B and 8 (19%, 95% confidence limits 12.9 to 25.0%) were F, whereas of the 41 typed cases from Santos, 39 (95%, 95% confidence limits 91.6 to 98.4%) were B and 2 (5%, 95% confidence limits 1.6 to 8.4%) were C. We therefore confirm the relationship between clade F and intravenous drug use in São Paulo, and the presence of clade C in Santos. The fact that different genetic subtypes of HIV-1 are co-circulating indicates a need for continuous surveillance for these subtypes as well as for recombinant viruses in Brazil.

HIV-1 infection among injection and ex-injection drug users from Rio de Janeiro, Brazil: prevalence, estimated incidence and genetic diversity

“…The hypothesis of a higher prevalence of HIV-1 subtype F infections in IDUs vis-a-vis other populations has been discussed by researchers from São Paulo (Rossini et al, 2001;Sabino et al, 1996). However, although a high prevalence of HIV-1 subtype F has been verified among the IDU population from Rio de Janeiro, our studies did not confirm any specific segregation pattern in the IDUs so far assessed (Guimarães et al, 2001).…”

Antiretroviral resistance and genetic diversity of human immunodeficiency virus type 1 isolates from the Federal District, Central Brazil

“…Thus it is important to monitor subtype profiles, as their distribution has local determinants, and data from one site cannot be generalized for the entire country or even for a single geographic region. HIV-1 subtype B is the most prevalent in our country, followed by subtype F1, with sporadic cases of subtypes C, D, and A (Rossini et al 2001, Gadelha et al 2003, Soares et al 2003.…”

High Levels of Primary Antiretroviral Resistance Genotypic Mutations And B/F Recombinants in Santos, Brazil

“…Previous studies analyzing samples from the city of Sao Paulo and surrounding areas have shown prevalences of 80% to 81% for subtype B, 0% to 10 for subtype C, 0% to 19% for subtype F, and 0% to 10% for B/U. 16,72 A recent study analyzing full-length HIV-1 genomes from 11 individuals with RI in Sao Paulo showed no relevant prevalence of clades other than B or recombinants (72.7% B and 18.2% B/F recombinants). 15 Monitoring the genetic diversity of HIV-1 in Brazil is central to understanding the molecular epidemiology and the spread of the epidemic.…”